Dispenser

ABSTRACT

The invention provides a dispenser which can be suspended over the rim of a toilet bowl to dispense a dose of active ingredient into the bowl as the bowl is flushed. The dispenser draws active liquid from a reservoir in discrete doses, each does being released by a pumping action which is caused by the action of the flush water on the dispenser. The dispenser includes a flow restrictor which normally prevents egress of the active liquid from the reservoir but which releases a dose under the influence of the pumping action.

FIELD OF THE INVENTION

This invention relates to a dispenser and, in particular, to a dispenseradapted for suspension from the rim of a toilet bowl to dispense one ormore active substances, such as cleansing and/or fresheningpreparations, into the bowl as the toilet is flushed.

BACKGROUND TO THE INVENTION

Devices suspended from the rims of toilet bowls, to dispense fresheningand/or cleaning preparations, are well known. In one form, such a devicecomprises a cage used to retain a replaceable block impregnated withdisinfectant and/or freshening agent. When the toilet is flushed, theflush water passes through the cage and degrades part of the block. Theactive substances from the block are entrained in the water and thuspass out into the toilet bowl.

More recently rim mounted toilet cleaning and freshening devices havebecome available which include a porous pad in communication with areservoir of a viscous liquid cleaning and freshening substance. Theliquid substance saturates the pad and is drawn out when flush water isdirected over the pad. As active cleaning liquid is flushed from thepad, further liquid is supplied from the reservoir to re-saturate thepad. An example of this type of device is described and claimed inEuropean Patent Application 0 785 315.

Existing liquid dispensing devices of the type disclosed in EP 0 785 315tend to be quite complex in design so as to prevent excess amounts ofactive substances emanating from the reservoir, collecting on thealready saturated pad, and dripping. Further, with existing products,the source of the active substances is in contact with the pad at alltimes and, between flushes re-saturates the pad. However, owing totypical viscosities of the active substances, it takes a period of time(typically 15 to 20 minutes) to re-saturate the pad after a flush. Thus,if the toilet is flushed in quick succession, insufficient activesubstance will have collected on the pad, and thus be released, toprovide efficacious results.

It is an object of this invention to provide a simple yet effective formof rim mounted toilet bowl dispenser which dispenses a viscous liquidactive substance but which addresses at least some of the drawbacksmentioned above; or which will at least provide a useful choice.

SUMMARY OF THE INVENTION

Accordingly, in a first aspect, the invention provides a dispenser forsuspension from the rim of a toilet bowl, said dispenser including:

-   -   a reservoir for containing a viscous liquid active substance;    -   a flow restrictor operable to limit the flow of said active        substance from said reservoir, said flow restrictor having an        inlet side and an outlet side,    -   said dispenser being characterised in that application of toilet        flushing water thereover creates a pumping action which operates        to displace at least one discrete dose of said active substance        through said flow restrictor.

Preferably said pumping action provides a pressure differential withinsaid dispenser to drive said active substance through said flowrestrictor.

Preferably said pumping action operates to displace a volume of airthrough said flow restrictor from the outlet side thereof, which volumeof air, in turn, displaces said at least dose of active substancethrough said flow restrictor from the inlet side thereof.

Preferably said dispenser is constructed and arranged so that, in itsnormal position of use, said active substance contacts the inlet side ofsaid flow restrictor under gravity.

Preferably said dispenser further includes at least one fluid dispensingsurface spaced from the outlet side of said flow restrictor from whichcomponents of said active substance can emanate. This dispensing surfaceis preferably positioned to receive active substance from said flowrestrictor under gravity.

Preferably said dispensing surface is provided as one or more wallsurfaces of a chamber positioned to receive active substance from saidflow restrictor. Said chamber is preferably formed, at least in part,from a porous material.

Preferably said chamber includes a substantially vertical peripheralwall and closing means at the bottom of said peripheral wall. Saidperipheral wall may be rectangular in cross-section but is preferablycylindrical. Said closing means is preferably formed integrally withsaid peripheral wall.

All wall sections of said chamber are preferably formed from said porousmaterial. Preferably said closing wall is thicker than said peripheralwall.

Said peripheral wall preferably has a thickness of substantially 2 mmand a porosity of 70 to 125 microns when used with an active preparationof viscosity 400 to 800 cPs.

Alternatively said vertical peripheral wall is non-porous, saiddispensing surface being defined by a porous pad or plate positioned incontact with, or closely adjacent, the lower edge of said peripheralwall.

Preferably said dispenser further includes venting means operable tomaintain a void on the outlet side of said flow restrictor betweenflushes.

Preferably said chamber further includes location means operable to fixthe alignment of said chamber with respect to said flow restrictor.Preferably said location means and said venting means are defined by acommon part of said chamber. This common part may comprise a slotdefined in said vertical peripheral wall.

Preferably said dispenser further includes ramp means constructed andarranged to direct water towards said chamber.

In a second aspect the invention provides a dispenser for suspensionfrom the rim of a toilet bowl to dispense active substance into a toiletbowl, said dispenser including:

-   -   a body member;    -   a reservoir for active substance included within or mountable on        said body member;    -   a dispensing surface positioned to receive active substance from        said reservoir and, upon flushing, to release said active        substance to flush water; and    -   release means operable to control the flow of active substance        from said reservoir to said dispensing surface,    -   said dispenser being characterised in that said release means is        operable to dispense at least one discrete dose of said active        substance on to said dispensing surface upon flushing of said        toilet.

In a third aspect the invention provides a dispenser for suspension fromthe rim of a toilet bowl to dispense active substance into the bowl,said dispenser including

-   -   a reservoir for active substance;    -   a dispensing surface positioned to receive active substances        from said reservoir and to release said active substance to        flush water when the toilet is flushed; and    -   release means to control the transfer of said active substance        from said reservoir to said dispensing surface,    -   said dispenser being characterised in that, in use, a void is        maintained between said reservoir and said dispensing surface        between flushes.

Preferably said dispensing surface is formed, at least in part, from aporous material. Preferably said porous material is shaped into acylinder with one end closed.

Preferably said dispenser is as hereinbefore set forth, wherein saidcylinder comprises said chamber.

Many variations in the way the invention may be performed will presentthemselves to those skilled in the art upon reading the followingdescription. The description which follows should not be regarded aslimiting but rather, as an illustration only of one mode of performingthe invention. Where possible, a description of any element or componentshould be taken as including any or all equivalents thereof whether ornot specifically mentioned. The scope of the invention should bedetermined solely by the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

One form of dispenser embodying the various aspects of the inventionwill now be described with reference to the accompanying drawings inwhich:

FIG. 1: shows a front elevational view of a dispenser according to theinvention;

FIG. 2: shows a view along the line II—II in

FIG. 3: shows a view, from above, of the dispenser shown in FIGS. 1 and2 with reservoir and suspension hook removed;

FIG. 4: shows a view, from below, of the dispenser shown in FIGS. 1 to3, with chamber and suspension hook removed;

FIG. 5: shows an enlarged view of part of the view shown in FIG. 2;

FIG. 6: shows a fluid receiving and emanating chamber for incorporationin the dispenser shown in FIGS. 1 to 5;

FIG. 7 shows a similar view to FIG. 2 but of an alternative embodimentof dispenser according to the invention; and

FIG. 8: shows an enlarged view of the area ringed in FIG. 7.

DETAILED DESCRIPTION OF WORKING EMBODIMENT

Referring firstly to FIGS. 1 to 6 of the drawings, the present inventionprovides a dispenser 5 which, in use and as is well known, is suspendedover the rim of a toilet bowl (not shown) so as to lie at least partlyin the path of flush water when the toilet is flushed. In theconventional manner, part of the flush water passing over the dispenserentrains substances contained therein, and carries these substances downinto the toilet bowl. The active substances typically comprise orinclude disinfectants, odour neutralisers, fragrances etc.

In the form shown, the dispenser comprises four main parts, a mouldedbody section 6, a detachable active substance reservoir 7, a dispensingsurface in the form of chamber 8, and a hook section 9. The hook section9 is preferably formed integrally with the body section 6, whilst thesubstance reservoir 7 and the chamber 8 are preferably separatecomponents which are engaged with the body section 6 and integral hooksection 9, to render the dispenser operable.

As can be seen in FIGS. 1 and 2, when in use, the reservoir 7 isinverted and engaged, via the outlet neck 10 thereof, over a hollowmounting spigot 1 projecting upwardly from the body section 6. The upperedge of the spigot 11 may, as shown, be formed into a barb 12 whichserves to pierce a frangible membrane (not shown) which is provided overthe outlet aperture of the reservoir, during manufacture thereof, toprevent leakage prior to use.

The spigot 11 has a central vertical bore 13 therethrough in which islocated a flow restrictor 14. In the form shown, the flow restrictorcomprises a simple plate having an inlet side 15, an outlet side 16, anda small central hole 17 therein. The hole 17 is sized having regard tothe viscosity of the active substance so as to ensure that, when activesubstance flows from the reservoir 7 under gravity and into contact withthe inlet side 15 of the restrictor 14, surface tension prevents flowthrough the hole 17. However, under the effect of the pumping actiongenerated when the toilet is flushed, at least one dose of the activesubstance is displaced through the hole 17.

Using an active substance with a viscosity in the range of 450 to 700cPs, we have found that a round hole 17 of 2 mm diameter providessatisfactory results. Having said that, satisfactory results are alsoachieved using an active substance of a viscosity as low as 120 cPs, inconjunction with a star shaped aperture having a net diameter of about 2mm.

Provided on the outlet side 16 of the flow restrictor is a small outletchannel 18.

Also located on the outlet side of the flow restrictor 14 is a fluiddispensing surface on which the unit of active substance dispensedthrough the flow restrictor can gather for subsequent removal by thetoilet flush water, and from which components of the active substance,such as fragrance, can emanate. In the form shown in FIGS. 1 to 6, thedispensing surface is incorporated in the walls of chamber 8 located inrecess 20 formed in the body part 6.

As can be seen, the chamber 8 is constructed and positioned to lie inthe path of the flush water when the dispenser is suspended from thetoilet rim in the known manner. At least part of the wall defining thechamber is formed from a porous material so that a dose of activesubstance passing through the flow restictor and collecting in thechamber 8 can permeate through parts of the chamber walls and gather onthe outer surface of the chamber. When the toilet is next flushed, theflush water entrains the active substance which has collected on theoutside of the chamber (and perhaps some which is still within thechamber wall but close to the outer surface) and the same out into thetoilet bowl. Between flushes, the dose of active substance entrained inthe chamber walls emanates fragrance to freshen the toilet environment.

In the particular embodiment depicted and described in FIGS. 1 to 6, thechamber 8 is oriented substantially vertically and all walls thereof aredefined by porous material. It will be noted, however, that the base orclosing wall 21 of the chamber is preferably thicker than the verticalwall sections 22. This results in the passage of active substancethrough the base being less (or slower) than passage through thevertical wall sections.

It will be noted from FIGS. 5 & 6, that the chamber 8 is also providedwith a vertical slot 23 extending down from the upper edge thereof, theslot 23 stopping short of the upper surface of the closing wall 21.This, in combination with the thicker section of the closing wall 21,reduces the likelihood of active substance dripping from the chamber 8between flushes. However, the principal purpose of the slot 23 is toensure rapid entry of the flush water into chamber 8, and rapid drainageof the same water therefrom. The rapid entry of the water into chamber 8is believed to generate a pumping action which pushes air through theflow restrictor and into reservoir 7. The air forced into the reservoir,in turn, displaces a dose of active substance back through the flowrestrictor 14. It may also be that the surge of flush water simplydisturbs the surface tension of the active substance where it covers theflow restrictor 14, thus allowing a unit dose of the active substance topass through the restrictor.

At the end of the flush, the water drains quickly through the slot 23and thus maintains a void between the source of active substance and thedispensing surface. This is important to prevent diffusion of water intothe active substance which would dilute and lower the viscosity of theactive substance, until ultimately rendering the system uncontrollable.

When the chamber 8 is mounted within recess 20 in the body section, theslot 23 is located about key 25 (FIG. 4) which closes across part of therecess 20. This ensures that, when the dispenser is mounted in itsoperative position beneath the rim of a toilet bowl, the slot 23 isaligned rewardly and in the general direction of the flow of flush waterdeflected over the dispenser. However, it is conceivable that thechamber 8 may be rotatable within the body section to allow the slot tobe positioned to eve a greater or lesser amount of flush water, therebyvarying the pumping action and amount of active substance leased perflush.

The precise geometric configuration of the chamber 8 can be varied. Inthe embodiment shown the vertical walls 22 are defined by a cylindricalwall section, but a rectangular arrangement could also be used. Thebenefit of the cylindrical section is that the chamber can be readilyand efficiently formed by boring a central hole 26 in a rod of porousmaterial. However, the chamber could be formed in a number ofalternative ways including cutting lengths of porous rod and pluggingone end thereof.

The chamber is preferably formed from sintered polypropylene materialmanufactured by Sintair Limited of Kings Lynn, Norfolk, England.

The performance of the dispenser as described herein is affected by thesize of the chamber 8, area of exposure to the flush water, materialporosity from which the chamber is formed, and the viscosity of theactive substance. In experimental testing, we have found thatsatisfactory results are achieved using a chamber having an outsidediameter of 12 mm, an inside diameter of 8 mm, a side wall thickness of2 mm and a base thickness of about 10 mm. When mounted in recess 20,about 20 mm of vertical wall section 22 is exposed below the bodysection. The chamber as above described is formed in a sintered materialhaving a mean porosity of 120 micron and preferably receives an activesubstance of ity in the range 120 to 700 cPs.

Obviously one can maintain an effective operating balance by varying theporosity of the chamber wall and also varying the viscosity of theactive substance and the diameter of hole 17.

The body section 6 includes a front face 30 and end walls 31 and 32which from an outer cage about the mounting spigot 11 and the chamber 8.The front face 30 includes apertures 33 therein to enhance the aestheticappearance of the dispenser and to allow flush water to pass out throughthe front surface of the dispenser. As can be seen in FIG. 1, the topedge 35 of the front face 30 is shaped to correspond to the form of theupper edge 36 of reservoir 7 so that the reservoir is neatly located andretained by body 6 when inverted and mounted on the body section 6.

The spigot 11 projects substantially vertically from a horizontalcentral web section 37 which extends rewardly of the front face 30 andeffectively spaces the front face 30, and side walls 31 and 32, forwardof the mounting point on a toilet bowl. To the rear, and below, the web37 are located a pair of downwardly directed ramp surfaces 38 a and 38 bwhich terminate in vertical apertures 39 facing the chamber 8. The rampsurfaces 38 a, 38 b serve to deflect flush water in the direction of thechamber 8 and may be provided with vanes 40 to further capture and alignthe flush water.

It will be further noted that the body section includes an intermediatewall section 41 which extends behind the body front surface 30 but infront of the chamber 8. This wall section 41 serves to ensure thechamber 8 is only contacted by active substance and flush water and, inparticular, cannot be “targeted” by males urinating in the toilet bowl.

Finally it will be noted that the suspension hook 9 extends from arearward extension of the central web section 37.

In use, the dispenser 5 is mounted beneath the rim of a toilet bowl, bysuspension hook 9, so that the front ace 30 is directed towards theinterior of the bowl. When the toilet is flushed, a proportion of thetoilet flush water circulating around the underside of the rim isdefected toward ramp surfaces 38 a and 38 b and, thereafter, throughapertures 39 and into contact with chamber 8. Since the slot 23 in thechamber 8 is awed substantially with the flush water steam, some flushwater will pass directly into the chamber causing a pumping action whichcauses a discrete dose of active substance to pass through hole 17 inthe flow restrictor 15, and down into the chamber 8. The dose of activepermeates through the chamber walls and releases fragrance and othervapour components. At the next flush, the dose is removed by the flushwater to pass into the toilet bowl and is replaced by another discretedose.

Turning now to FIGS. 7 and 8, a dispense r 50 is shown for dispensingdiscrete doses of active substance from reservoir 51. As with theembodiment described above, the dispenser includes a hook section 52which is configured, and operates identically, to the hook section 9 ofthat embodiment.

Indeed the dispenser 50 is in most respects identical to the dispenser5. The only important difference is that the porous chamber 8 isreplaced by a non-porous peripheral wall section 53, defining chamber54, which operates in conjunction with a porous pad 55, the pad 55 beingin contact with, or positioned closely adjacent to, the lower edge 56 ofthe wall section 53.

In the form shown, the front face 57 of the dispenser is formed into arearwardly aligned ledge 58 at the lower end thereof. The ledge 58, incombination with the lower edge 56 of the wall section 53, and the loweredge of intermediate wall section 59, defines a clipping slot whichretains the pad 55 in position.

As with the porous chamber 8, the peripheral wall section 53 includes arearwardly aligned, vertically extending slot 60 which, as shown,extends the full height of the wall section 53. This allows flush waterto enter the chamber 54 and create the pumping action in the mannerdescribed above.

The use and operation of the dispenser 50 is identical to that ofdispenser 5 described above. The advantage of the dispenser 50, overdispenser 5, is that the pad 55 generally provides a greater surfacearea than porous chamber 8, from which fragrances can emanate, betweenflushes.

Whilst the predominant pumping action is believed to be a positivedisplacement of air within chamber 8, 54 and channel 18 into thereservoir 7, 51 causing active substance to be displaced back throughthe hole 17, the rapid passage of flush water over the outlet channel18, as well as the rapid drainage of flush water through slot 23, 60may, in addition, create venturi effect of suction which draws activethrough the hole 17. Obviously the configuration of the dispenser hereindescribed could be varied to enhance the venturi or suction effect.

It is also possible to provide an air bleed tube up through thereservoir to vent the headspace within the reservoir, to the voidbeneath the flow rector 14.

Whatever the precise dose release action way be, we have found that adispenser as above described displays the following attributes:

-   -   1) Efficacious rest are achieved with each flush, no matter how        close together the Rushes in contrast to prior art dispensers        which take considerable time to recover to    -   2) The toilet and surrounding areas are freshened continuously;    -   3) One or more discrete doses of active are released each flush        ensuring constant performance over the life of the contents of        the reservoir.

It will thus be appreciated that the present invention provides a simpleyet effective form of rim mounted dispenser for dispensing activesubstances into a toilet bowl.

1. A dispenser for suspension from the rim of a toilet bowl to dispenseviscous liquid active substance into a stream of water created when thetoilet is flushed, said dispenser including: a reservoir containing saidviscous active substance within an interior thereof, a body sectionsupporting said reservoir and for releasing a dose of said viscousactive substance from said reservoir, under gravity, when the toilet isflushed; a flow restrictor having an inlet side in communication withthe interior of said reservoir an outlet side, and at least one apertureextending between said inlet side and said outlet side, said aperturebeing sized to, in combination with the viscosity of said activesubstance, restrain said active substance by surface tension fromflowing under gravity from said reservoir; an outlet channel extendingfrom said outlet side and being in direct communication with said atleast one aperture; and ramp surfaces on said body section to directsaid stream of water toward said outlet channel, wherein in use, saidstream of water is directed into said outlet channel and into contactwith said outlet side of said flow restrictor, overcomes said surfacetension and effects the release of a dose of said viscous activesubstance from said reservoir.
 2. A dispenser as claimed in claim 1further including at least one fluid dispensing surface spaced from theoutlet side of said flow restrictor from which components of said activesubstance can emanate.
 3. A dispenser as claimed in claim 2 wherein saiddispensing surface is positioned to receive active substance from saidflow restrictor under gravity.
 4. A dispenser as claimed in claim 2wherein said dispensing surface is provided as one or more wall surfacesof a chamber positioned to receive active substance from said flowrestrictor.
 5. A dispenser as claimed in claim 4 further including rampmeans constructed and arranged to direct water towards said outlet side.6. A dispenser as claimed in claim 4 wherein said chamber is formed, atleast in part, from a porous material.
 7. A dispenser as claimed inclaim 4 wherein said chamber includes a substantially verticalperipheral wall.
 8. A dispenser as claimed in claim 7 wherein saidperipheral wall is cylindrical.
 9. A dispenser as claimed in claim 1wherein an outlet side of said flow restrictor is defined by anon-porous peripheral wall section in combination with a porous bottomsurface.
 10. A dispenser as claimed in claim 1 further including ventingmeans operable to maintain a void on the outlet side of said flowrestrictor between flushes.